TY - JOUR
T1 - 1,25-Dihydroxyvitamin D induces lipoprotein lipase expression in 3T3-L1 cells in association with adipocyte differentiation
AU - Vu, Diane
AU - Ong, John M.
AU - Clemens, Thomas L.
AU - Kern, Philip A.
PY - 1996
Y1 - 1996
N2 - 1,25-dihydroxyvitamin D3 [1,25-(OH)2D3] is known to modulate the development of hone and other mesenchymal cell types. Since osteoblasts and adipocytes are thought to arise in bone marrow from a common progenitor, this work examined the effects of 1,25-(OH)2D3 on adipocyte development, and in particular on the expression of lipoprotein lipase (LPL), which is an early marker for the differentiated adipocyte. 3T3-L1 preadipocytes were cultured in the presence of 1.25-(OH)2D3 (10-9 to 10-7 M) for up to 7 days. LPL activity was measured in the medium and cell extracts, and LPL messenger RNA levels were measured by Northern blotting. When compared to control cells, 10-7 M 1,25-(OH)2D3 increased medium LPL activity by 2- to 3-fold and cellular LPL by 1.5-fold. Significant increases in medium and cellular LPL were observed at 10-9 M and were maximal at 10-7 M. Along with the increase in LPL activity, there was an increase in LPL messenger RNA by 2- fold at 5 days, and by 5-fold at 7 days. In addition to an increase in LPL, 1,25-(OH)2D3 increased expression of aP2, an adipocyte-specific marker associated with differentiation. After the addition of 1,25-(OH)2D3, there was a decrease in 3T3-L1 cell number, which is consistent with differentiation, and a decrease in vitamin D receptors. Finally, these cells developed a different morphology. 1,25-(OH)2D3-treated cells assumed a rounded appearance, although without detachment from the dish and without the degree of lipid accumulation usually associated with the addition of insulin, isobutylmethylxanthine, and dexamethasone. It is concluded that 1,25- (OH)2D3 induced LPL expression in 3T3-L1 cells through an induction of differentiation-dependent mechanism(s). These findings suggest an important role for 1,25-(OH)2D3 in normal adipocyte differentiation.
AB - 1,25-dihydroxyvitamin D3 [1,25-(OH)2D3] is known to modulate the development of hone and other mesenchymal cell types. Since osteoblasts and adipocytes are thought to arise in bone marrow from a common progenitor, this work examined the effects of 1,25-(OH)2D3 on adipocyte development, and in particular on the expression of lipoprotein lipase (LPL), which is an early marker for the differentiated adipocyte. 3T3-L1 preadipocytes were cultured in the presence of 1.25-(OH)2D3 (10-9 to 10-7 M) for up to 7 days. LPL activity was measured in the medium and cell extracts, and LPL messenger RNA levels were measured by Northern blotting. When compared to control cells, 10-7 M 1,25-(OH)2D3 increased medium LPL activity by 2- to 3-fold and cellular LPL by 1.5-fold. Significant increases in medium and cellular LPL were observed at 10-9 M and were maximal at 10-7 M. Along with the increase in LPL activity, there was an increase in LPL messenger RNA by 2- fold at 5 days, and by 5-fold at 7 days. In addition to an increase in LPL, 1,25-(OH)2D3 increased expression of aP2, an adipocyte-specific marker associated with differentiation. After the addition of 1,25-(OH)2D3, there was a decrease in 3T3-L1 cell number, which is consistent with differentiation, and a decrease in vitamin D receptors. Finally, these cells developed a different morphology. 1,25-(OH)2D3-treated cells assumed a rounded appearance, although without detachment from the dish and without the degree of lipid accumulation usually associated with the addition of insulin, isobutylmethylxanthine, and dexamethasone. It is concluded that 1,25- (OH)2D3 induced LPL expression in 3T3-L1 cells through an induction of differentiation-dependent mechanism(s). These findings suggest an important role for 1,25-(OH)2D3 in normal adipocyte differentiation.
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U2 - 10.1210/endo.137.5.8612483
DO - 10.1210/endo.137.5.8612483
M3 - Article
C2 - 8612483
AN - SCOPUS:0029978733
SN - 0013-7227
VL - 137
SP - 1540
EP - 1544
JO - Endocrinology
JF - Endocrinology
IS - 5
ER -